The delivery of personalized news content depends on the ability to predict user interests. We evaluated different methods for acquiring user profiles based on declared and actual interest in various news topics and items. In an experiment, 36 students rated their interest in six news topics and in specific news items and read on 6 days standard, nonpersonalized editions and personalized (basic or adaptive) news editions. We measured subjective satisfaction with the editions and expressed preferences, along with objective measures, to infer actual interest in items. Users' declared interest in news topics did not strongly predict their actual interest in specific news items. Satisfaction with all news editions was high, but participants preferred the personalized editions. User interest was weakly correlated with reading duration, article length, and reading order. Different measures predicted interest in different news topics. Explicit measures predicted interest in relatively clearly defined topics such as sports, but were less appropriate for broader topics such as science and technology. Our results indicate that explicit and implicit methods should be combined to generate user profiles. We suggest that a personalized newspaper should contain both general information and personalized items, selected based on specific combinations of measures for each of the different news topics. Based on the findings, we present a general model to decide on the personalization of news content to generate personalized editions for readers.

Providing adaptive help during interaction with the system can be used to assist users in accomplishing their tasks. We propose providing guidance by highlighting the steps required for performing a task that the user intends to complete according to the prediction of a system. We present a study aimed at examining whether highlighting intended user steps in menus and toolbars as a means of assisting users in performing tasks is useful in terms of user response and performance. We also examined the effects of different accuracy levels of help and the control format on user response and performance. An experiment was conducted in which 64 participants performed tasks using menus and toolbars of a simulated email application. Participants were offered a highlighted guidance of the required steps in varying levels of accuracy (100%, 80%, 60% and no guidance). Our results support the benefits of highlighted help both in user performance times and in user satisfaction from receiving such assistance. Users found the assistance necessary and helpful and by the same token not unduly intrusive. Additionally, users felt that such assistance generally helped in reducing performance time on tasks. We did not find a significant difference when users receiving help at 80% accuracy was compared to those receiving help at 100% accuracy; however, such a difference does appear for those receiving 60% accuracy. In such cases, we found that the user's satisfaction level, perceived usefulness and trust in the system decreased while their notion of perceived intrusiveness increased. We conclude that assisting users by highlighting the required steps is useful so long as the minimal accuracy level of help is higher than 60%. Our study has implications on the implementation of highlighting next steps as a means of adaptive help and on integrating probability-based algorithms such as intention prediction to adaptive assistance systems.

This study evaluated aesthetics and usability of in-vehicle electronic navigation maps. Experiment 1 examined map displays that varied in the amount of information presented, abstraction level, graphic/colour style and the existence of landmarks in both urban and rural environments using objective and subjective measures. Twenty participants performed navigation/localisation tasks using various map configurations while driving a driving simulator and completed usability and aesthetic questionnaires. The minimal detail map produced better performances and higher usability and aesthetic ratings when using maps with no landmarks. Adding information in the form of landmarks was found advantageous compared to additional textual information. Abstractions were most advantageous when combined with minimal amount of detail. Moderate abstractions were sufficient for obtaining the desired benefits when more details were present. The graphic/colour style affected subjective perceptions. Overall, high correlations were found for the perceived aesthetics and usability scales, however, low correlations were found between actual usability (i.e. performance) and perceived usability pointing to the importance of using both objective and subjective usability measures. Experiment 2 examined how maps varying in their aesthetic level (aesthetic versus non-aesthetic), different colour arrangements, and 2D versus 3D landmarks affect subjective and objective measures. Participants distinguished between usability and aesthetic perceptions and usability perceptions were less affected by aesthetics when the aesthetic level of the maps was low. Colour arrangement did not affect the measures examined. Both 2D and 3D landmarks were found to be aesthetic and usable. We conclude this article with guidelines for designing in-vehicle navigation map displays.

The aim of this study was to examine how users perceive help on a mobile device with respect to the presentation format and the severity of the scenario the user encounters. We examined how 92 participants responded to four different formats of help offered for five different scenarios varying in their severity level using static images displayed in a web browser. The intrusiveness of the help format and the severity of the scenario affected participants' interest in receiving help. In certain conditions it may be helpful to suggest help, in particular when users do not know how to ask for it but show interest in receiving it when offered.